The -F option of off_align aligns a face on the
brick with a face on the base
and then uses it to augment or excavate the base model (the polyhedra
are joined and the bonding faces removed). This operation can be
repeated symmetrically with the -y option.
In this example a tetrahedron is aligned with a face of an icosahedron.
The default alignment causes the tetrahedron to lie outside the
icosahedron, producing an augmentation.
The bonding operation is repeated with the
symmetry of the base model by specifying -y full.
View this model with the command
off_align -F tet -y full icosahedron | antiview